Refrigeration apparatus



Ap '27, 1943. c. F. ALslNG REF'nLurJKATLON APPARATUS Filed Dec. 10, 1941INVENTOR (7424 ALS/NG ATTOR Y Patented A r. 27, 1943 UNlTED STATESPATENT OFFICE REFRIGERATION APPARATUS Carl'F. Alsing, Wilbraham, Mass,assignor -to Westinghouse Electric 8; Manufacturing Company, EastPittsburgh, Pa, a. corporation of Pennsylvania Application December 10,1941, Serial No. 422,342

Claims.

This invention relates to refrigerating apparatus and more especially toapparatus adapted to maintain a food-storage compartment at ahigh-humidity.

One object of' the invention is to provide a thermal storage capacityfor an intermittentlyoperating refrigerating system.

Another object of the invention is. to decrease the fluctuation in thetemperature of the foodstorage compartment caused by anintermittently-operating refrigerating apparatus.

Theseandother objects are effected by my innism 25 interposed in one oftwo leads 33 which supply the electric motor 42 in the casing 21 withvention as will be apparent from the following description and claimstaken in accordance with the accompanying drawing, forming a part ofthis application, in which:

Fig. l is an elevation of a domestic refrigerator with parts broken awayto show the refrigerating system of this invention; and

Fig. 2 is an enlarged sectional view of the thermal storage tank of thisinvention.

Referring to the drawing for a detailed description of the invention,the reference numeral ill designates a refrigerating cabinet comprisingan outer metal 'shell' Ii. The shell is divided by a horizontalpartition i2 into an upper foodstorage compartment l3 and a machinecompartment l4 below the food-storage compartment l3.

1 The food-storage compartment I3 is provided with an inner metal linerl6. Heat-insulating material I1 is packed between the inner liner i6 andthe upperportion of the metal shell II and the partition l2. Thefood-storage compartment [3 is further divided by a horizontal partitionl8 into an upper low-temperature, lowhumidity compartment l9 and ahigh-humidity compartment 2| below the low-humidity compartment l9.

electric power. The switch mechanism 25 is of the snap-acting type andpreferably'has a temperature differential of 10 Fahrenheit in order toprevent an excessive number of starts of the nects through tubes and 36with a secondary refrigerant condenser comprising a horizontally coiledtube 31 located in the thermal storage tank 3! and spaced from the coil29. The top area of the high-humidity compartment 2| is alsorefrigerated by conduction through the partition l8.

The thermal storage tank 3| contains a liquid 39, the upper level ofwhich is indicated by the A primary refrigerant evaporator 22 is locatedin the low-humidity compartment and is provided with primary refrigerantliquid through a capillary tube 23 and a coil 29 from a primaryrefrigerant condenser 24. The condenser 24 receives compressedrefrigerant vapor through a tube 26 from a compressor driven by anelectric motor 42, both the compressor 4|! and the electric motor 42being housed in a sealed casing 21. The compressor 40 withdrawsrefrigerant vapor through a suction tube 29 from the primary evaporator22. The coil 29 is located in a thermal storage tank 3| and forms asecond evaporator in series with the primary evaporator 22.

The refrigerating apparatus 22, 24, and 40 is operated intermittently tomaintain the temperaturelof the primary evaporator 22 between, forexample, 0 and 30 Fahrenheit. To this end a bulb l5 containing avolatile liquid is aiiixed in heat transfer relationship with theprimary evaporator 22. The bulb l5 communicates through a tube 29 withan electric switch mechadotted'line 4|. The liquid comprises a solutionof, for example, alcohol or glycerin and water, the solution preferablyhaving a freezing point of from 15 to 25? Fahrenheit depending on thequantity of the liquid which is frozen.

Operation The coil 29 forms an evaporative cooling unit fluctuating intemperature between 0 and 30 Fahrenheit with the active and inactiveperiods of the primary refrigerating apparatus 22, 24, and 40. When theprimary refrigerating apparatus 22, 24, and 40 is active, and thetemperature of the coil 29 is below 15 Fahrenheit, portions of'theliquid 39 will freeze. During the freezing of the liquid 39, the latentheat of the frozen portion thereof is transmitted to the coil 29, sothat the refrigerating efiect of'the coil 29 is not directed entirely tolowering the tem-'- perature of the secondary condenser coil 31. Thiskeeps the unit running at higher suction pressure with bettereillciency.

In like manner, when the refrigerating apparatus 22, 24, and 40 isinactive between operating The absorption of heat-from the coil 31 tendsto continue its action as a condenser for the secondary refrigerant tocool the coil 34.

The full cooling efiect of the primary refriger- 'ant coil 28 is thusnot transmitted toward the cooling of the secondary refrigerant coil 31-andthe secondary refrigerant evaporator 34 during the active cycle ofthe refrigerating apparatus 22, 24, and I because a portion of thecooling effect surfaces, and means "for conveying heat from saidsecondary cooling unit to said thermal storage liquid, said thermalstorage liquid having a congealing point of such temperature thatasubstantial portion of the liquid congeals when said means supplies saidsecond primary cooling unit with refrigerant and melts when said meansdoes of the coil 29 is stored by the formation of' a 1 frozen solutionin the thermal storage tank 3|. During the inactive period of therefrigerating apparatus 22, 24, and 40, the frozen solution melts andabsorbs heat from the. secondary refrigerant condenser 31, therebytomaintain the temperature in the high-humidity compartment 2| moreuniform to overcome the effect of cycling of the refrigerating apparatus22, 24, and 40.

The more uniform temperature of the high humidity storage compartment 2|permits of a higher humidity therein, because less of the moisture inthe air of the compartment 2| is condensed on the portion of the innerliner iii of the compartment 2| during the active cycle of therefrigerating apparatus 22,24, and 40, because of the higher temperatureof the inner liner during the active cycle.

It will be apparent from the above that this invention provides thermalstorage for an intermittently operating refrigerating system whichstorage decreases the fluctuations in the tem- V perature of thehigh-humidity food-storage compartment and makes possible themaintenance of a higher humidity therein.

While I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications without departing from the spiritthereof, and I desire, therefore, that only such limitations shall beplaced there upon as are specifically set forth in the appended .claims.

What r claim is: 1. In refrigerating apparatus, the combination of'aninsulated cabinet defining a low-humidity and a high-humiditycompartment, a thermal storage liquid, a primary cooling unit forcooling the low-humidity compartment and the thermal storage liquid,means for intermittently supplying the primary cooling unit withrefrigerant to maintain the temperature of said primary cooling unitbetween predetermined limits, a secondary evaporative cooling unit forcooling the highhumidity compartment, said secondary evaporative coolingunit having extended heat-absorbing and a condenser for said secondaryvevaporative cooling lmit, said condenser being in heat-transferrelationship with said thermal storage liquid, saldther'mai storageliquid having a congealing point of suchtemperature that a substantialportion of the liquid congeals when said means supplies the rimarycooling unit with refrigerant and melts when said means does not supplythe primary cooling unit with refrigerant.

not supply the second primary cooling unit with refrigerant. o

3. In refrigerating apparatus, the combination of an insulated cabinetdefining a low-humidity and a high-humidity compartment, a primarycooling unit for cooling the low-humidity compartment, a second primarycooling unit for cooling a thermal storage liquid, means forintermittently supplying said cooling units with reand primary coolingunit with refrigerant and melts when said means does not supply'the second primary cooling unit with refrigerant.

4. In refrigerating apparatus, the combination of a cabinet, a metalliner therein, said cabinet defining a low-humidity and a high-humiditycompartment, a primary cooling unit for cooling the low-humiditycompartment, a second primary cooling unit for cooling a thermal-storageliquid, meansfor intermittently supplying said cooling units withrefrigerant, a. secondary cooling unit in heat-transfer relationshipwith a large portion of the-metal linear of the high-humiditycompartment, and means for conveying heat from said secondary coolingunit to said thermal-storage liquid; said thermal-storage liq-- uidhaving a congealing point of such temperature that a substantial portionof theliquid congeals when said means supplies said second pri- 2. Inrefrigerating apparatus, the combination of an insulated cabinetdefining a low-humidity and a high-humidity compartment, 8. primarycooling lmit for cooling the low-humidity compartment, a second primarycooling unit for cooling a thermal storage liquid, means forintermittently supplying said cooling units with refrig'erant, asecondarycooling unit for cooling the high-humidity compartment, saidsecondary cooling unit having extended heat-absorbing mary cooling unitwith refrigerant andmelts when said means does not supply the secondprimary cooling unitwith refrigerant.

5.\ In refrigerating apparatus, the combination of a cabinet,heat-insulating material surrounding said cabinet, a chamber located insaid heatinsulating material, a thermal-storage liquidin said chamber, apartition in said'cabinetto divide,

the same into two food-storage compartments, a primary cooling zmit forcooling one of said compartments, a second primary cooling unit forcooling said thermal-storage liquid,-means for intermittently supplyingsaid primary cooling units with refrigerant, a secondary cooling .unitfor cooling the other of said compartments, said secondary cooling unithaving extended heatabsorbing surfaces, and means for conveying heatfrom said secondary cooling unit tosa'id thermalstorage liquid, saidthermal-storage liquid having a congealing point of such temperaturethat a substantial portion of the liquid congeals when said meanssupplies said second primary cooling unit with refrigerant and meltswhen said means does not supply said second primary cooling unit withrefrigerant.

' CARL F. ALSING.

